There's quite a number of water cycles about, some rigid float, and one or two with inflatable booms so pack away. One is designed to stow on a roof rack.
There's pedal kayaks too, some users have done very long trips along rivers using them in both Canada and Australia. One of the most popular pedal kayaks uses rear paddle vanes like a platypus or whale's tail. The pedals flap them up and down, propelling it forward.
Our bike designer Mike Burrows did a test report on one of them a little while ago.
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